Microelectronic devices, such as semiconductor devices and field emission displays, are generally fabricated on and/or in microelectronic workpieces using several different types of machines (“tools”). Many such processing machines have single or multiple processing stations that perform one or more procedures on the workpieces. For example, some existing machines include a plurality of electrochemical processing chambers, each of which is configured to contact a microelectronic workpiece with an electrochemical processing fluid to deposit material (such as an electrically conductive material) on the microelectronic workpiece.
One characteristic of both single and multiple processing station tools is that the rates and efficacies of processes performed in the chambers are dependent upon the flow rate of electrochemical processing fluid into the chambers. One problem with this characteristic is that the flow rate of fluid into the processing chambers can fluctuate. For example, existing electrochemical processing chambers typically include an in-line filter to remove impurities from the electrochemical processing fluid. As the filter accumulates particulates and other contaminates, the pressure of the fluid exiting the filter decreases, as does the fluid flow rate. As the fluid flow rate decreases, rate-dependent processes, such as the rate at which material is deposited onto the microelectronic workpiece, also decrease, which can lead to undesirable variations in the processed workpieces.